基于交易成本理论，探讨不同控制权分配情况下，合资承诺对公告公司股票收益的影响。本文以2009年至2013年间发布合资公告的上市公司为研究对象，利用事件研究法和多元回归分析方法，研究股票市场对合资公告的反应。实证结果显示，股票市场对合资公告具有积极的正向反应，股票收益随着投资承诺的增加而增加，但与时间承诺的关系并不显著。当伙伴掌握绝对控制权时，投资承诺对公告公司股票收益的边际贡献率最高，权力平衡的分配模式次之，最低的为公告公司掌握绝对控制权的情况。本研究从控制权分配角度，解释了合资承诺与企业绩效之间的关系，为管理者提供了关于合资投入和控制权分配的决策参考。

This study aims to distinguish the effects of joint venture commitment on stock market returns according to the distribution of control based on transaction cost theory. Based on a sample of listed firms who formed joint ventures between 2009 and 2013, we examine the value effects of joint venture announcements using event study and regression analysis. Results show that stock market positively rewards joint venture announcements, and the abnormal return will increase with the aggregation of investment commitment. No significant relationship has been found on time commitment and stock returns. Further, joint ventures controlled by partner firms will be valued more by stock investors than shared control or focal firm control. We complement the existing knowledge of commitment and focal firm performance by including control as a conditional variable. This paper has great implications for managers on making investment and control decisions.